1. Field of the Invention
The present invention generally relates to fruit juice extractors, and more particularly, the present invention relates to a high speed citrus fruit juice extractor of the type wherein a citrus fruit is compressed between opposing cups that have fingers that interdigitate as the cups are brought together.
2. Description of the Prior Art
U.S. Pat. No. 2,649,730 to J. M. Hait and No. 2,780,988 to W. C. Belk et al disclose a type of high speed citrus juice extractor that utilizes a process of extraction wherein a hole is cut through the peel of a fruit to be extracted and then the entire surface of the fruit is compressed between a pair of cups to force the juice and pulpy internal material of the fruit (section membranes, seeds and core) through such hole. The cups include circumferentially spaced fingers which each form a hemispherical cavity and which are adapted to interdigitate as they are brought together to form a progressively smaller chamber to thereby compress the fruit. The internal portions of the fruit forced through said hole in the peel flow into a strainer tube without coming into contact with the outer peel. As the cups are brought together, a hollow orifice tube is progressively extended toward the cups within the strainer tube to force the juice through the perforations in the strainer tube and to eventually capture the pulpy material within the upper end of the orifice tube. In the prior art extractors of the interdigitating cup type, a plurality of pairs of cups are aligned to be driven by a common drive mechanism and all of the movable upper cups are rigidly attached to cup shafts which, in turn, are rigidly connected in a linear arrangement to a crosshead. The crosshead is driven by a cam arrangement so that all upper cups (usually three to five in number) are simultaneously driven to extract juice from seveal fruits at a time.
This type of extractor has been very popular due to the fact that, with the exception of a small hole cut through the peel, the peel is not cut prior to extraction, nor is the juice brought into contact with the outer peel, thereby minimizing the possibility of peel oil mixing with the juice being extracted. The oil exuded from the peel during extraction remains outside of the peel and is collected by an oil recovery system. This type of extractor is thus capable of producing high quality citrus peel oil concurrently with the extraction of citrus juice.
Although the extractor shown in the U.S. Pat. Nos. 2,780,998 and 2,649,730 has functioned very satisfactorily, it is subject to several shortcomings. With the rise in popularity of citrus juice food products in recent years, the citrus juice producers have demanded that juice extractors be adapted to operate at higher production rates. It has been found that the prior art juice extractor of the type just described is capable of satisfactorily operating at a maximum rate of 100 fruit per cup per minute. Thus, to increase productivity, it has been heretofore necessary to increase the number of extractors, which of course requires more floor space and thus often requires very costly plant expansion.
Another problem associated with the prior art extractor concerns its efficiency of operation. As previously indicated, in the prior art extractor, the upper cups are mounted to a crosshead and the crosshead is driven to simultaneously compress several fruit between the several upper and lower cups of the extractor. It is further noted that all of the orifice tubes in such extractor are mounted to a crosshead that is driven by pull rods connected to the upper cup crosshead. The extractor will be understood to operate like a punch press. It requires a great amount of power to simultaneously extract juice from the several fruit. The main camshaft is first subjected to a large torque in one rotative direction as the cups and orifice tubes are driven toward each other; and thereafter, upon the reversal of movement of the tubes and cups, the main camshaft undergoes a rapid and drastic torque reversal due to the action of return springs.
Yet another problem associated with the prior art extractor concerns the high noise level generated thereby. Heretofore, the only apparent means for reducing such high noise level was to provide an insulated container (or shield) for enclosing such drive mechanisms. Vibration also caused problems with the prior art extractors and required that the frame be securely bolted down.